With the most performant tires:
Assetto Corsa lap time in 2:13.26 (It would be the WR on RSR, but I haven't been able to score the lap time, because the application has stopped working (it tells me to update to the latest version, i did but it continues to ask me to update ..))
Project Cars lap time in 2:06.95 (WR in the leaderboard)
With old tires:
Assetto Corsa 2:19.678
Project Cars 2:13.70

Why this big difference?
I think it is mainly due to the track. in AC it is in laser scan, in PCars is well made but not scanned. Probably there is some difference.